[v0.4.0] 2019-12-16

Enhancements:

• Adding support for customizing markdown styles - https://github.com/GetStream/stream-chat-react-native/pull/99/files#diff-ede54911d9164ea37e65e92f2e18cb91R56
• Replacing text property theme with textContainer.

Breaking change:

text property has been removed from theme message.content, so it won't work anymore. It has been replaced with textContainer to make it explicit that you are styling a View and not a Text component.